Among the different types of protein glycosylation, C-mannosylation of tryptophan residues stands out because of the unique linkage formed between sugar and protein. Instead of the typical O- or N-glycosidic linkage, a C-C bond is used for attachment of a single mannose. C-mannose is characteristically found in thrombospondin type 1 repeats and in the WSXWS motif of type I cytokine receptors.
View Article and Find Full Text PDFAlg3 of Saccharomyces cerevisiae catalyzes the mannosyl transfer from Man-P-Dol to Man(5)GlcNAc(2)-PP-Dol resulting in the formation of Man(6)GlcNAc(2)-PP-Dol, which is then further processed to the final precursor oligosaccharide Glc(3)Man(9)GlcNAc(2) for N-glycosylation of proteins. Here, we identified the alg3 gene of the mushroom-forming fungus Schizophyllum commune by homology search. Its function was confirmed by the complementation of the Δalg3 strain of S.
View Article and Find Full Text PDFDeficiency of β-1,4 mannosyltransferase (MT-1) congenital disorder of glycosylation (CDG), due to ALG1 gene mutations. Features in 9 patients reported previously consisted of prenatal growth retardation, pregnancy-induced maternal hypertension and fetal hydrops. Four patients died before 5 years of age, and survivors showed a severe psychomotor retardation.
View Article and Find Full Text PDFCongenital disorders of glycosylation type I (CDG-I) form a growing group of recessive neurometabolic diseases. Identification of disease genes is compromised by the enormous heterogeneity in clinical symptoms and the large number of potential genes involved. Until now, gene identification included the sequential application of biochemical methods in blood samples and fibroblasts.
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